rmonad provides a restricted monad class in the Control.RMonad hierarchy.
The class makes use of associated datatypes (available in GHC 6.8),
using an idea learnt from Wolfgang Jeltsch:
http://www.haskell.org/pipermail/haskell-cafe/2008-March/041084.html
It also provides a way to treat a restricted monad as a normal monad
using a generic wrapper type. This idea is described here:
http://hsenag.livejournal.com/11803.html?nc=5
See the haddock documentation for information on how to use it.
TODO
Add instances for all the mtl stuff. Consider also doing this for mtl-tf
(namespacing issues?)